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841.
A Roman archaeological site in northern Spain (La Maja, province of La Rioja) includes pottery workshops, part of an important ceramic industry that developed from about the first century BC to the first century AD. A geophysical study was planned to determine the extent of the industrial complex in the vicinity of an excavated kiln. Magnetic observations were done on a grid of 30 × 36m, with a sampling interval of 1m. Two dipolar-shaped anomalies were found: one in the north-east and the other in the south-west of the area. Low-pass and band-pass filters were used in the Fourier domain to enhance the characteristics of the magnetic data and to remove noise and undesirable shallow features. Three-dimensional polygonal prisms were used to model the magnetic anomalies based on palaeomagnetic measurements performed over an uncovered kiln that helped to constrain the induced and remanent parameters of the magnetizing fields.  相似文献   
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846.
In recent decades, many Appalachian households have experienced declining incomes due to the loss of traditional male jobs in the mining and manufacturing sectors. One response to this decline has been an increase in female employment in formal sector activities. Another response is homework, or the home-based production of goods and services for sale in the formal and informal sectors. In rural Appalachia, where formal jobs are often unavailable or inadequate to support a household, many women are engaging in homework as an economic strategy. Consequently, economic restructuring cannot be fully understood without analyzing household strategies and gender relations. This paper examines the intersection of gender, households, and economic restructuring as it relates to women's homework and employment shifts in rural Appalachia. Research for this paper entailed qualitative interviews with 50 West Virginia women who are engaged in the home-based production of goods and services. The study analyzes the variety of homework activities done by rural women, their contribution to household incomes, and the effect of these activities on gender relations and divisions of labor in the home. The research forwarded in this study advances a conceptual understanding of household economic strategies and has some practical applications for women and economic development in underdeveloped regions .  相似文献   
847.
ABSTRACT This paper extends the research of Hyclak and Johnes (1989) in analyzing the relationship between the rigidity in real wages and state unemployment rates. It presents evidence contrary to the empirical findings of Hyclak and Johnes in that measures of real wage rigidity are not robust over time in explaining changes in state unemployment rates. Moreover, an alternative proxy accounting for divergent growth patterns across states does not significantly affect changes in state unemployment rates.  相似文献   
848.
ABSTRACT. Data for 28 metropolitan areas over a 15-year period are used to determine the impacts of government spending, taxes, and public infrastructure on total employment and disaggregated employment. After carefully controlling for the government budget constraint we find that taxes are negatively related to total employment and education spending is positively related to total employment. Nevertheless, we find that it is difficult for metropolitan areas to influence the composition of their employment with government tax and expenditure policies. Moreover, at current levels of public infrastructure, marginal changes in infrastructure have no strong effect on employment.  相似文献   
849.
ABSTRACT. The problem of locating a point that is as far as possible from arcs and nodes of a network is investigated. Each arc or node may have a different multiplicative factor (weight) for its distance. A graphical solution approach, as well as a computational algorithm, is presented.  相似文献   
850.
ABSTRACT. A large proportion of regional production takes place in nontraded goods and services. In addition, significant productivity increases can be observed in some segments of this sector. Starting from these two empirical observations we construct a model of growth in a two-region setting with factor mobility. The growth process is based on endogenous technological change in the nontraded input sector, whose output serves as an input in the production of one of the two final goods, the so-called industrial good. We consider two extreme cases, one with locally limited, the other with interregional knowledge spillovers. Conditions are established under which interior solutions with production of local inputs and steady-state growth in both regions result, and others under which we find a core-periphery pattern with growth concentrated in one region only. The stability of the equilibria is discussed by considering the transition processes. Finally, it is shown that catching-up as well as leapfrogging may occur, if new technologies become available.  相似文献   
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